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History of Microsoft's Windows Operating System (OS)

2006

Windows (v7) Vista (Feb)

1 Kor Kilo = 1 Thousand or 1,000
1 M or Mega = 1 Million or 1,000,000
1 G or Giga = 1 Billion or 1,000,000,000
1 T or Terra = 1 Trillion or 1,000,000,000,000
1 P or Peta = 1 Quadrillion or 1,000,000,000,000,000
1 E or Exa = 1 Quintillion or 1,000,000,000,000,000,000

Numbers:
Computers store information in bits. A bit is a number that can be either 1 or 0. All digital devices boil down to this! Bits in themselves have limited use so a byte was defined which is a collection of 8 bits. Using the binary (0-1), as opposed to our dinary (0-9) number system a byte can represent any number between 0-255. These numbers are then used to represnt letters and other characters, e.g. the letter A is actually stored as the number 65 in a byte or as a computer knows it 01000010. Whenever we describe how much memory something is capable of storing we always describe this in terms of Bytes or 'B' for short. Numbers larger than 255 are made possible by joining 2 or 4 or 8 bytes together; these groups of bytes are called Words. A four byte word (equating to 32 bits) can represent any number from 0 - 4,294,967,295 (or about 4 Billion). Today these numbers are used to generate different amplitudes of electricity to produce the sounds from your CD player to your mobile phone, colours and dots you see on your computer screen, TV or DVD player and the movement from joysticks or gamepads, to robotic toys or machines.

Storing numbers:
Today computers store numbers in blocks of 32 or 64 bit Words, but we still describe the total amount of memory in Bytes. These numbers are stored in several ways. Initially they were stored as holes in paper tape (back in the 1950s), but now we store this information as either; pits on a CD or DVD, magnetic polarity on Hard Disk Drives; and most importantly as electrical charge stored on tiny transister circuites within a silicon chip. Always the information is stored as a collection of 1's or a 0's, on or off, North or South, hole or no hole. A CD for instance holds about 70 minutes of music, because it is really storing numbers, the information of the disk can be anything; files; pictures or sounds. A CD can store up to 800 Million Bytes (remember 1 Byte can store one letter even without compression this is a lot of information, equating to ) which equates to about 6.4 Billion Bits or 1's and 0's. In about another 2 years there will be a new disc to superceed the DVD which will be able to hold about 40 Billion Bytes (or 40 Giga Bytes as we call it in computer speak). Of course different types of media require different amounts of memory to store them; 1 letter needs 1 byte of information, a typical book if compressed would need 50,000 Bytes (50kB) which is about, a colour photo requires about 50,000 to 500,000 Bytes (500kB) depending on the detail required; a single (3 minutes of music) compressed requires about 6,000,000 Bytes or 6MB). So you can get about 7 hours of compressed music (MP3 format) on one CD. New ways of compressing sounds, pictures, movies and text are being developed all the time, squeezing more and more information into a fixed amount of memory.

Speed:
Computers are not just about storing information but also about processing it. The more information you have and the numbers it takes to display, play or moving it, the faster the processor needs to be, the faster you need to be able get the information from memory. Hence the biggest factors in a computers speed are the 'Processor' (CPU chip), the speed of the Hard Disk and memory chips, and the speed of the Graphics processor (particualrly important for fast action games). Information is moved around in a computer on the stroke of a clock, the faster the clock the faster the computer, but the various parts of the computer must be able to keep up with the clock. Today clocks run at about a few Billion ticks or cylces per second, a cycle is refered to in Herts or Hz for short, so 1 Billion cycles per second is described as 1 Giga Herts or 1GHz. Hard disks are being pushed faster and faster, disks currently spin at about 7200 revs per minute, however it still takes about a hundredth of a second for the head to be moved to the right part of the disk to read the information (a long time in computer terms), hence the memory on silicon chips (or SIMMs or DIMMs as they are known) is still a lot faster as information can be retreived from anywhere in the memory in a fraction of a millionth of a second. And because SIMMs are more expensive for storing the same amount of information as Hard Disks SIMMs are used for a computer's short term memory and for processing information and Hard Disks for the long term memory storage.

Sending and receiving numbers:
Moving information from one device to another becomes important when the number of different types of devices is increasing exponantally along the amount of information to be moved. The more information can be moved from one place to another in a set amount of time the better. To compair these speeds we talk about the number of bits ('b' as opposed to Bytes 'B') that can be transfered per second this is abreviated as bps. To gage how many Bytes per second you must divide the amount of bps by about 10 (it would be 8 but 10 is easier and there are other overheads in communicating information). New faster international standards for transfering information are being thrashed out and agreed all the time. So there are many technologies to communicate information all with there own pro's and con's. Here are the most common ones below.

IP (Internet Protocol) is a language that is used to help computers talk to each other over different types of technologies like those listed above. It is the language of the Internet. Carrying messages or information from one machine, on one side of the world, to another computer on the other side. To enable the many millions of computers to be able to talk with each other their must be large devices that act like junctions on a road network, directing information down different routes these devices are called IP Routers and Switches and it is these devices that allows the global network of the internet to function. (This is huge and complex subject and as it happens my speciality which I have taught for 6 years, anyway I will not bore you any longer).

History of the PC (Personal Computer) & related technology

Intel Pentium II introduced
V.90 Modem introduced

2004